This week’s headlines: Facebook Rolls Out Graph Search, Twitter Introduces Ad Retargeting, Yelp Diversifies with Booking Services, Instagram Allows Embedding of Content, LinkedIn Overhauls Mobile Search and Vine Releases Major Update.

The week’s news quick hits: Google Reader Closes Down, Facebook Hashtags Get Additional Features, Former Xbox Lead Takes Helm at Zynga, Yahoo Acquires Qwiki, Instagram Adds Landscape Mode, Facebook Adds Folders to Home, Twitter Adds Direct Message Syncing, Tumblr Updates Mobile Apps for Content Discovery, Foursquare Now Available for One of World’s Most Popular Phones and Zynga Announces Real-Money Gambling Games for the UK.